Post-abortion menstrual period refers to the onset of menstruation, which changes from 7 days to 4 days, and is considered normal as long as there are no other abnormal manifestations. Under normal circumstances, the duration of a woman’s menstrual period is usually about 3 to 7 days. Before the abortion, the duration of the menstrual period was 7 days, and after the menstrual period, the duration of the menstrual period changed to 4 days, which is within the normal range, and as long as there are no other abnormal manifestations, it is considered a normal phenomenon. After the miscarriage, the duration of menstrual flow is obviously abnormal, for example, the duration of menstrual flow is more than 7 days or less than 3 days, and this situation occurs repeatedly, there may be abnormalities, for example, uterine adhesion, polycystic ovary syndrome, and so on. If the menstrual period after abortion is too short or too long and there are other abnormalities, it is recommended to consult a doctor for examination and treatment.